一组数据5,-2,3,5,-2,3的方差

问题描述:

一组数据5,-2,3,5,-2,3的方差

求出平均数
(5-2+3+5-2+3)÷6
=2
方差
=[(5-2)^2+(-2-2)^2+(3-2)^2+(5-2)^2+(-2-2)^2+(3-2)^2]÷6
=(9+16+1+9+16+1)/6
=8.67